RADIATIVE COOLING AND BROADBAND PHENOMENON IN LOW-FREQUENCY WAVES

FU Zun-tao; JIANG Xun; QIAO Fang-li; LIU Shi-kuo

Abstract:

In this paper, we analyze the effects of radiative cooling on the pure baroclinic low-frequency waves under the approximation of equatorial β-plane and semi-geostrophic condition. The results show that radiative cooling does not, exclusively, provide the damping effects on the development of low-frequency waves.Under the delicate radiative-convective equilibrium, radiative effects will alter the phase speed and wave period,and bring about the broadband of phase velocity and wave period by adjusting the vertical profiles of diabaticheating. When the intensity of diabatic heating is moderate and appropriate, it is conductive to the development and sustaining of the low-frequency waves and their broadband phenomena, not the larger, the better. The radiative cooling cannot be neglected in order to reach the moderate and appropriate intensity of diabatic heating.

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FU Zun-tao, JIANG Xun, QIAO Fang-li, et al. RADIATIVE COOLING AND BROADBAND PHENOMENON IN LOW-FREQUENCY WAVES [J]. Journal of Tropical Meteorology, 2000, 6(1): 75-85.

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RADIATIVE COOLING AND BROADBAND PHENOMENON IN LOW-FREQUENCY WAVES

Department of Geophysics, Peking University, Beijing 100871 China SKLTR, Peking University, Beijing, 100871, China

Department of Geophysics, Peking University, Beijing 100871 China

First National Institute of Oceanography Key Laboratory of Marine Science and Numerical Modeling, Qingdao 266000, China

Received Date: 1999-02-28

Rev Recd Date: 2000-02-03

Abstract: In this paper, we analyze the effects of radiative cooling on the pure baroclinic low-frequency waves under the approximation of equatorial β-plane and semi-geostrophic condition. The results show that radiative cooling does not, exclusively, provide the damping effects on the development of low-frequency waves.Under the delicate radiative-convective equilibrium, radiative effects will alter the phase speed and wave period,and bring about the broadband of phase velocity and wave period by adjusting the vertical profiles of diabaticheating. When the intensity of diabatic heating is moderate and appropriate, it is conductive to the development and sustaining of the low-frequency waves and their broadband phenomena, not the larger, the better. The radiative cooling cannot be neglected in order to reach the moderate and appropriate intensity of diabatic heating.

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RADIATIVE COOLING AND BROADBAND PHENOMENON IN LOW-FREQUENCY WAVES

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